Phase-change materials (PCM) are capable of transforming from a crystalline phase to an amorphous phase. These two solid phases exhibit differences in electrical properties, and semiconductor devices can advantageously exploit these differences. Given the ever-increasing reliance on radio frequency (RF) communication, there is particular need for RF switching devices to exploit phase-change materials. However, the capability of phase-change materials for phase transformation depends heavily on how they are exposed to thermal energy and how they are allowed to release thermal energy. For example, in order to transform into an amorphous phase, phase-change materials may need to achieve temperatures of approximately seven hundred degrees Celsius (700° C.) or more, and may need to cool down within hundreds of nanoseconds. In order to rapidly cool down phase-change materials (PCM), heat must be dissipated from a PCM RF switch by using heat spreading techniques.
Unique requirements for materials, fabrication steps and design layouts for PCM RF switches may pose design challenges for other components and circuits in large scale integration with PCM RF switches. Other components of a semiconductor device in RF applications, such as resonators utilized in RF filters and oscillators, have their own requirements for materials, fabrication steps, and design layouts. Large scale integration of resonators may not be easily compatible with PCM RF switches using conventional fabrication techniques. For example, various modifications in design layout, materials and fabrication steps have significant impact on thermal energy management and can decrease the reliability of PCM RF switches. Specialty manufacturing is often impractical, and large scale manufacturing generally trades practicality for the ability to control performance characteristics of PCM RF switches and resonators.
Thus, there is need in the art for effective and practical large scale integration of PCM RF switches with resonators.